Process for manufacturing an intraocular lens with an embedded mask

ABSTRACT

Intraocular implants and methods of making intraocular implants are provided. The intraocular implant can include a mask adapted to increase depth of focus. The method of manufacturing the implant can include positioning the mask with an aperture on a protruding pin of a positioning mold portion. The protruding pin can be configured to center the mask in the intraocular lens.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.15/815,017, filed on Nov. 16, 2017, which is a continuation of U.S.patent application Ser. No. 15/427,456, now U.S. Pat. No. 9,844,919,filed on Feb. 8, 2017, which is a continuation of U.S. patentapplication Ser. No. 15/133,139, now U.S. Pat. No. 9,573,328, filed onApr. 19, 2016, which is a divisional of U.S. patent application Ser. No.13/830,889, now U.S. Pat. No. 9,427,922, filed on Mar. 14, 2013, whichis hereby incorporated by reference in its entirety.

BACKGROUND Field

This application relates generally to the field of intraocular devices.More particularly, this application is directed to intraocular implantsand lenses (IOLs) with an aperture to increase depth of focus (e.g.“masked” intraocular lenses), and methods of making the same.

Description of the Related Art

The human eye functions to provide vision by transmitting and focusinglight through a clear outer portion called the cornea, and furtherrefining the focus of the image onto a retina by way of a crystallinelens. The quality of the focused image depends on many factors includingthe size and shape of the eye, and the transparency of the cornea andthe lens.

The optical power of the eye is determined by the optical power of thecornea and the crystalline lens. In a normal, healthy eye, sharp imagesof distant objects are formed on the retina (emmetropia). In many eyes,images of distant objects are either formed in front of the retinabecause the eye is abnormally long or the cornea is abnormally steep(myopia), or formed in back of the retina because the eye is abnormallyshort or the cornea is abnormally flat (hyperopia).

Some people suffer from cataracts in which the crystalline lensundergoes a loss of transparency. In such cases, the crystalline lenscan be removed and replaced with an intraocular lens (IOL). However,some intraocular lenses may still leave defects in a patient'snon-distance eyesight.

SUMMARY

Certain aspects of this disclosure are directed toward a method ofmanufacturing an intraocular lens. The method can include adding a firstamount of a lens material to a first lens forming mold portion. Themethod can include positioning a mask with an aperture on a protrudingpin of a positioning mold portion. The protruding pin can be configuredto center the mask in the intraocular lens. The method can includejoining the first lens forming mold portion and the positioning moldportion. The method can include partially curing the first amount of thelens material. Any of the mold features, intraocular lens or maskfeatures, steps, or processes disclosed in this specification can beincluded in any embodiment.

In the above mentioned method aspect, the lens material can include anultraviolet light absorber and a light-sensitive initiator. Theinitiator can be configured to cure the lens material when exposed tolight having a wavelength outside the absorption spectrum of theultraviolet light absorber. In certain aspects, the initiator can beconfigured to be activated by light having a wavelength in a range fromabout 380 nm to about 495 nm.

In any of the above mentioned method aspects, positioning the mask onthe protruding pin can include positioning the mask adjacent to ashoulder portion of the protruding pin having a diameter larger than theaperture of the mask. The shoulder portion can be configured to controlthe depth of the mask in the intraocular lens.

In any of the above mentioned method aspects, joining the first lensforming mold portion and the positioning mold portion can cause lensmaterial to flow into a space between a surface of the mask and an innersurface of the positioning mold portion from which the protruding pinextends so as to at least partially surround the mask with lens materialon both of its sides.

In any of the above mentioned method aspects, partially curing the firstamount of the lens material can include applying light to the first lensforming mold portion.

In any of the above mentioned method aspects, partially curing the firstamount of the lens material can include curing the first amount of thelens material less than 50% of a full cure but to a sufficient degreethat the mask remains with the first lens forming mold portion afterremoving the positioning mold portion.

In any of the above mentioned method aspects, the method can includecooling the first lens forming mold portion. The cooling process canhelp bias the mold set such that the lens material and mask remain inthe first lens forming mold portion when the mold portions areseparated. Other methods of biasing the mold set can include, but arenot limited to, forming the first lens forming mold portion from amaterial that adheres to the lens material to a greater extent than thepositioning mold portion material.

In any of the above mentioned method aspects, the method can includeremoving the positioning mold portion and joining the first lens formingmold portion and a second lens forming mold portion.

In any of the above mentioned method aspects, the method can includeadding a second amount of the lens material to the second lens formingmold portion. In certain aspects, the method can include partiallycuring the second amount of the lens material less than 50% of a fullcure by exposure to light. In certain aspects, the method can include,after partially curing the second amount of the lens material byexposure to light, thermally curing the second amount of the lensmaterial.

In any of the above mentioned method aspects, the method can includepolymerizing at least 99% of the first and second amounts of the lensmaterial.

In any of the above mentioned method aspects, the lens material can be ahydrophobic material.

In any of the above mentioned method aspects, the method can includejoining a haptic shield and the positioning mold portion such that thehaptic shield prevents polymerization of the lens material in a hapticregion.

Certain aspects of this disclosure are directed toward a mold set formanufacturing an intraocular lens having a mask suspended within theintraocular lens. The mold set can include a first lens forming moldportion configured to hold at least a portion of a lens material. Themold set can include a positioning mold portion configured to positionthe mask within the lens material. The positioning mold portion can beconfigured to mate with the first lens forming mold portion. Thepositioning mold portion can include a body portion and a protruding pinextending from the body portion. An end portion of the protruding pincan have a first diameter sized to correspond to an aperture in themask. The protruding pin can be configured to control centration of themask within the lens material. In certain aspects, the protruding pincan include a shoulder portion having a second diameter that is largerthan the first diameter. The shoulder portion can be configured tocontrol the depth of the mask within the lens material. Any of the moldfeatures, intraocular lens or mask features, steps, or processesdisclosed in this specification can be included in any embodiment.

In the above mentioned mold aspect, the length of the protruding pin canbe sized such that the end portion of the protruding pin extends within0 mm to 0.2 mm from the lens forming surface of the first lens formingmold portion when the positioning mold portion is joined with the firstlens forming mold portion.

In any of the above mentioned mold aspects, a length of the protrudingpin can be configured such that an optical zone of the intraocular lensis substantially free of the lens material when the first mold portionmates with the positioning mold portion.

In any of the above mentioned mold aspects, the second diameter of theshoulder portion can be about 50% of an outer diameter of the mask.

In any of the above mentioned mold aspects, the shoulder portion can beconfigured such that the lens material can flow between a surface of themask and the body portion.

In any of the above mentioned mold aspects, the mold can include asecond lens forming mold portion configured to hold another portion ofthe lens material and join with the first lens forming mold portion.

In any of the above mentioned mold aspects, the first lens forming moldportion can include a haptic region. In certain aspects, the mold caninclude a haptic shield positioned on the positioning mold portion suchthat the haptic shield blocks curing light from reaching the hapticregion so as to prevent polymerization of the lens material within thehaptic region.

For purposes of summarizing the disclosure, certain aspects, advantagesand features of the inventions have been described herein. It is to beunderstood that not necessarily any or all such advantages are achievedin accordance with any particular embodiment of the inventions disclosedherein. No aspects of this disclosure are essential or indispensable.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A illustrates a top view of an example embodiment of anintraocular lens having an embedded mask for improving depth of focus.

FIG. 1B illustrates a cross-sectional view of the intraocular lens ofFIG. 1A taken along line 1B-1B.

FIG. 2A is a perspective view of one embodiment of a mask configured toincrease depth of focus.

FIG. 2B is a perspective view of an embodiment of a substantially flatmask configured to increase depth of focus.

FIG. 3A is a top view of another embodiment of a mask configured toincrease depth of focus.

FIG. 3B is an enlarged view of a portion of the view of FIG. 3A.

FIG. 3C is a cross-sectional view of the mask of FIG. 3B taken alongline 3C-3C.

FIGS. 4A-4D illustrate the cross-sectional views of an embodiment of amold set.

FIG. 5 is a flow chart illustrating an embodiment of a method for makingan intraocular lens using the mold set illustrated in FIGS. 4A and 4B.

FIG. 6 is a flow chart illustrating another embodiment of a method formaking an intraocular lens using the mold set illustrated in FIGS. 4Aand 4B.

DETAILED DESCRIPTION

As discussed herein, people who undergo intraocular lens (IOL)implantation surgery may still suffer from defects in their non-distanceeyesight. One technique for treating such defects is by including a maskwithin the IOL that increases the patient's depth of focus. Theintraocular implants of the embodiments described herein include a maskadapted to provide a small aperture for light to pass through to theretina to increase depth of focus. The light rays that pass through themask within the IOL converge at a single focal point on the retina,while the light rays that would not converge at the single point onretina are blocked by the mask. This disclosure describes methods formanufacturing a lens, such as an IOL, having an embedded mask.

Several alternatives to fixed-focus IOLs have been developed, includingmultifocal IOLs and accommodating IOLs, that attempt to provide theability to see clearly at both near and far distances. However,accommodating IOLs can be complex and some multifocal IOLs do notperform well at intermediate distances and cause glare, halos, and nightvision difficulties associated with the presence of unfocused light.This limitation can force designers of multifocal optics to choose howmuch of the light is directed to each focal point, and to deal with theeffects of the unfocused light that is always present in any image. Inorder to maximize acuity at the important distances of infinity (>6M)and 40 cm (normal reading distance), it is typical to provide little orno light focused at an intermediate distance, and as a result, visualacuity at these distances is poor. With a mask that includes an apertureto increase depth-of-focus, however, the intermediate vision of apatient can be improved significantly. For example, the defocus blurassociated with the aperture can be less at intermediate distances thanat near.

FIGS. 1A-B illustrate an example embodiment of an intraocular lenshaving an embedded mask 1008 for increasing depth of focus. Theintraocular lens 1000 includes haptics 1004 for positioning the lenswithin the eye. The cross-sectional thickness of the lens body 1002 isgenerally dependent on the optical power of the intraocular lens 1000and the material of the lens body 1002. In particular, the centralregion of the lens body 1002 is generally the thickest section of theintraocular lens 1000 with a central region cross-sectional thickness1006. Methods for reducing the thickness of the intraocular lens aredescribed in U.S. Pub. No. 2011/0040376, filed Aug. 13, 2010, which ishereby incorporated by reference in its entirety.

The intraocular lens and/or the lens body can be made from one or morematerials. In certain embodiments, the intraocular lens material caninclude a hydrophobic material and/or a low-viscosity material. Forexample, in certain embodiments, the lens material can include ahydrophobic co-polymer such as those disclosed in U.S. Pat. No.7,067,602, filed Jun. 27, 2006, which is hereby incorporated byreference in its entirety. In other embodiments, the intraocular lensand/or the lens body can comprise polymers (e.g. PMMA, PVDF,polypropylene, polycarbonate, PEEK, polyethylene, acrylic copolymers,polystyrene, PVC, polysulfone), hydrogels, or silicone.

In certain embodiments, the lens material can include an ultravioletlight absorber to provide protection for the eye. The intraocular lensbody can be configured to permit less than about 10% of lighttransmission at 370 nm, less than about 5% of light transmission at 370nm, less than about 1% of light transmission at 370 nm, or otherwise.

In certain embodiments, the intraocular lens can have a bi-convex designand/or can be configured to have a power range from at least about 12.5diopter to less than or equal to about 30 diopter. In certainembodiments, the refractive index at 589 nm can be between about 1.481and/or 1.487, between about 1.481 and/or 1.484, or otherwise. In certainembodiments, the refractive index at 546 nm can be between about 1.483and/or 1.489, between about 1.482 and/or 1.484, or otherwise. In certainembodiments, the lens body can have a shore A hardness of at least about90 and/or less than or equal to about 95. In certain embodiments, thelens body can have a shore A hardness of about 93.

Masks

A variety of variations of masks that can be positioned on or within theimplant body are discussed herein, and also described in U.S. Pat. No.7,628,810, U.S. Patent Publication No. 2006/0113054, and U.S. PatentPublication No. 2006/0265058, all of which are hereby incorporated byreference in their entirety. FIG. 2A illustrates one embodiment of amask 2034 a. The mask 2034 a can include an annular region 2036 asurrounding an aperture 2038 a substantially centrally located on themask 2034 a. The aperture 2038 a can be generally located around acentral axis 2039 a, referred to herein as the optical axis of the mask2034 a. The aperture 2038 a can be in the shape of a circle. FIG. 2Billustrates another embodiment of a mask 2034 b similar to the mask 2034a illustrated in FIG. 2A. The annular region 2036 a of the mask 2034 aof FIG. 2A has a curvature from the outer periphery to the innerperiphery of the annular region 2036 a, while the annular region 2036 bof the mask 2034 b of FIG. 2B can be substantially flat.

The mask can have dimensions configured to function with the implantbody to improve a patient's vision. For example, the thickness of themask can vary depending on the location of the mask relative to theimplant body. For example, if the mask is embedded within the implantbody, the mask can have a thickness greater than zero and less than thethickness of the implant body. Alternatively, if the mask is coupled toa surface of the implant body, the mask may preferably have a thicknessno greater than necessary to have desired opacity so that the mask doesnot add additional thickness to the intraocular lens.

The mask may have a constant thickness, as discussed below. However, insome embodiments, the thickness of the mask may vary between the innerperiphery (near the aperture 2038 a,b) and the outer periphery.

The annular region 2036 a,b can be at least partially opaque or can becompletely opaque. The degree of opacity of the annular region 2036 a,bcan prevent at least some or substantially all light from beingtransmitted through the mask 2034 a,b. Opacity of the annular region2036 a,b can be achieved in any of several different ways.

For example, in some embodiments, the material used to make mask 2034a,b can be naturally opaque. In some embodiments, the material used tomake the mask 2034 a,b can be substantially clear, but treated with adye or other pigmentation agent to render region 2036 a,b substantiallyor completely opaque. In some embodiments, the surface of the mask 2034a,b can be treated physically or chemically (such as by etching) toalter the refractive and transmissive properties of the mask 2034 a,band make it less transmissive to light.

The material of the mask 2034 a,b can be, for example, any polymericmaterial. Where the mask 2034 a,b is applied to the intraocular implant,the material of the mask 2034 a,b should be biocompatible. Examples ofsuitable materials for the mask 2034 a,b can include, but are notlimited to, highly fluorinated polymers, such as PVDF, hydrogels, orfibrous materials, such as a Dacron mesh.

In some embodiments, a photochromic material can be used as the mask orin addition to mask. Under bright light conditions, the photochromicmaterial can darken thereby creating a mask and enhancing near vision.Under dim light conditions, the photochromic material can lighten, whichallows more light to pass through to the retina. In certain embodiments,under dim light conditions, the photochromic material lightens to exposean optic of the intraocular implant. Further photochromic materialdetails are disclosed in U.S. patent application Ser. No. 13/691,625,filed Nov. 30, 2012, which is hereby incorporated by reference in itsentirety.

The mask can have different degrees of opacity. For example, the maskcan block substantially all of visible light or a portion of visiblelight. The opacity of the mask can also vary in different regions of themask. In certain embodiments, the opacity of the outer edge and/or theinner edge of the mask can be less than the central region of the mask.The opacity in different regions can transition abruptly or have agradient transition. Additional examples of opacity transitions can befound in U.S. Pat. Nos. 5,662,706, 5,905,561 and 5,965,330, all of whichare hereby incorporated by reference in their entirety.

Further mask details are disclosed in U.S. Pat. No. 4,976,732, issuedDec. 11, 1990, U.S. Pat. No. 7,628,810, issued Dec. 8, 2009, and in U.S.patent application Ser. No. 10/854,032, filed May 26, 2004, all of whichare hereby incorporated by reference in their entirety.

FIGS. 3-4 show another embodiment of a mask 2100 configured to increasedepth of focus of an eye of a patient with presbyopia. The mask 2100 canbe similar to the masks hereinbefore described, except as describeddifferently below. The mask 2100 can be made of the materials discussedherein, including those discussed above. In addition, the mask 2100 canbe formed by any suitable process. The mask 2100 can be configured to beapplied to and/or embedded in an IOL.

In some embodiments, the mask 2100 can include a body 2104 that has ananterior surface 2108 and a posterior surface 2112. The body 2104 can beformed of any suitable material, including, but not limited to, at leastone of an open cell foam material, an expanded solid material, and/or asubstantially opaque material. In some embodiments, the material used toform the body 2104 can have relatively high water content. In someembodiments, the materials that can be used to form the body 2104include polymers (e.g. PMMA, PVDF, polypropylene, polycarbonate, PEEK,polyethylene, acrylic copolymers (e.g., hydrophobic or hydrophilic),polystyrene, PVC, polysulfone), hydrogels, silicone, metals, metalalloys, or carbon (e.g., graphene, pure carbon).

In some embodiments, the mask 2100 can include a hole arrangement 2116.The hole arrangement 2116 can include a plurality of holes 2120. Theholes 2120 are shown on only a portion of the mask 2100, but the holes2120 can be located throughout the body 2104 in some embodiments. Themask 2100 can include an outer periphery 2124 that defines an outer edgeof the body 2104. In some embodiments, the mask 2100 can include anaperture 2128 at least partially surrounded by the outer periphery 2124and a non-transmissive portion 2132 located between the outer periphery2124 and the aperture 2128.

The mask 2100 can be symmetrical, e.g., symmetrical about a mask axis2136. In some embodiments, the outer periphery 2124 of the mask 2100 canbe circular. The mask in general can have an outer diameter of at leastabout 3 mm and/or less than about 6 mm. In some embodiments, the mask iscircular and can include a diameter of at least about 3 mm and/or lessthan or equal to about 4 mm. In some embodiments, the mask 2100 iscircular and can include a diameter of about 3.2 mm.

In some embodiments, one of the anterior surface 2108 and the posteriorsurface 2112 of the body 2104 can be substantially planar. In someembodiments, very little or no uniform curvature can be measured acrossthe planar surface. In some embodiments, both of the anterior andposterior surfaces 2108, 2112 can be substantially planar. In general,the thickness of the body 2104 of the mask 2100 can be within the rangeof from greater than zero to about 0.5 mm, about 1 micron to about 40microns, in the range from about 5 microns to about 20 microns, orotherwise. In some embodiments, the body 2104 of the mask 2100 caninclude a thickness 2138 of at least about 5 microns and/or less than orequal to about 20 microns. In some embodiments, the body 2104 of themask can include a thickness 2138 of at least about 5 microns and/orless than or equal to about 15 microns. In certain embodiments, thethickness 2138 can be about 15 microns, about 10 microns, about 8microns, about 5 microns, or otherwise.

A substantially planar mask can have several advantages over anon-planar mask. For example, a substantially planar mask can befabricated more easily than one that has to be formed to a particularcurvature. In particular, the process steps involved in inducingcurvature in the mask 2100 can be eliminated.

The aperture 2128 can be configured to transmit substantially allincident light along the mask axis 2136. The non-transmissive portion2132 can surround at least a portion of the aperture 2128 andsubstantially prevent transmission of incident light thereon. Asdiscussed in connection with the above masks, the aperture 2128 can be athrough-hole in the body 2104 or a substantially light transmissive(e.g., transparent) portion thereof. The aperture 2128 of the mask 2100can generally be defined within the outer periphery 2124 of the mask2100. The aperture 2128 can take any of suitable configuration, such asthose described above.

In some embodiments, the aperture 2128 can be substantially circular andcan be substantially centered in the mask 2100. The size of the aperture2128 can be any size that is effective to increase the depth of focus ofan eye of a patient with presbyopia. In particular, the size of theaperture 2128 can be dependent on the location of the mask within theeye (e.g., distance from the retina). In some embodiments, the aperture2128 can have a diameter of at least about 0.85 mm and/or less than orequal to about 2.2 mm. In certain embodiments, the diameter of theaperture 2128 is less than about 2 mm. In some embodiments, the diameterof the aperture is at least about 1.1 mm and/or less than or equal toabout 1.6 mm. In some embodiments, the diameter of the aperture is atleast about 1.3 mm and/or less than or equal to about 1.4 mm.

The non-transmissive portion 2132 can be configured to preventtransmission of visible light through the mask 2100. For example, insome embodiments, the non-transmissive portion 2132 can preventtransmission of substantially all or at least a portion of the spectrumof the incident visible light. In some embodiments, the non-transmissiveportion 2132 can be configured to prevent transmission of substantiallyall visible light, e.g., radiant energy in the electromagnetic spectrumthat is visible to the human eye. The non-transmissive portion 2132 cansubstantially prevent transmission of radiant energy outside the rangevisible to humans in some embodiments.

As discussed above, preventing transmission of light through thenon-transmissive portion 2132 can decrease the amount of light thatreaches the retina and the fovea that would not converge at the retinaand fovea to form a sharp image. As discussed above, the size of theaperture 2128 is such that the light transmitted therethrough generallyconverges at the retina or fovea. Accordingly, a much sharper image canbe presented to the retina than would otherwise be the case without themask 2100.

In some embodiments, the non-transmissive portion 2132 can preventtransmission of at least about 90 percent of incident light. In someembodiments, the non-transmissive portion 2132 can prevent transmissionof at least about 95 percent of all incident light. The non-transmissiveportion 2132 of the mask 2100 can be configured to be substantiallyopaque to prevent the transmission of light.

In some embodiments, the non-transmissive portion 2132 can transmit nomore than about 5% of incident visible light. In some embodiments, thenon-transmissive portion 2132 can transmit no more than about 3% ofincident visible light. In some embodiments, the non-transmissiveportion 2132 can transmit no more than about 2% of incident visiblelight. In some embodiments, at least a portion of the body 2104 isconfigured to be opaque to more than 99 percent of the light incidentthereon.

As discussed above, the non-transmissive portion 2132 may be configuredto prevent transmission of light without absorbing the incident light.For example, the mask 2100 could be made reflective or could be made tointeract with the light in a more complex manner, as discussed in U.S.Pat. No. 6,554,424, issued Apr. 29, 2003, which is hereby incorporatedby reference in its entirety.

As discussed above, the mask 2100 can include a plurality of holes 2120.When the mask is formed embedded in the lens body, the lens body canextend at least partially through the holes, thereby creating a bond(e.g. material “bridge”) between the lens body on either side of themask. Further disclosure regarding the material “bridge” can be found inU.S. Publication No. 2011/0040376, filed Aug. 13, 2010, which is herebyincorporated by reference in its entirety.

The holes 2120 of the mask 2100 shown in FIG. 3A can be located anywhereon the mask 2100. In some embodiments, substantially all of the holesare in one or more regions of a mask. The holes 2120 of FIG. 3A extendat least partially between the anterior surface 2108 and the posteriorsurface 2112 of the mask 2100. In some embodiments, each of the holes2120 includes a hole entrance 2160 and a hole exit 2164. The holeentrance 2160 is located adjacent to the anterior surface 2108 of themask 2100. The hole exit 2164 is located adjacent to the posteriorsurface 2112 of the mask 2100. In some embodiments, each of the holes2120 extends the entire distance between the anterior surface 2108 andthe posterior surface 2112 of the mask 2100. Further details aboutpossible hole patterns are described in WO 2011/020074, filed Aug. 13,2010, which is hereby incorporated by reference in its entirety.

In some embodiments, the mask 2100 can include an annular region nearthe outer periphery 2124 of the mask having no holes. In certainembodiments, there are no holes within 0.1 mm of the outer periphery2124 of the mask 2100.

In some embodiments, the mask can include an annular region around theinner periphery of the mask having no holes. In certain embodiments,there are no holes within 0.1 mm of the aperture 2128.

In some embodiments, the holes 2120 each have a same diameter. Incertain embodiments, the holes 2120 can include one or more differentdiameters. In some embodiments, the diameter of any single hole 2120 isat least about 0.01 mm and/or less than or equal to about 0.02 mm. Insome embodiments, the diameter of the holes 2120 can include one or moreof the following hole diameters: 0.010 mm, 0.013 mm, 0.016 mm, and/or0.019 mm. In some embodiments, holes of different diameters areinterspersed throughout at least a portion of the mask 2100. In someembodiments, the holes are interspersed at irregular locationsthroughout at least a portion of the mask 2100.

In some embodiments there are at least about 1000 holes and/or less thanor equal to about 2000 holes. In some embodiments, there are at leastabout 1000 holes and/or less than or equal to about 1100 holes. In someembodiments, there are about 1040 holes. In some embodiments, there arean equal number of holes of each diameter. In some embodiments, thenumber of holes having each diameter is different.

In some embodiments, the holes are interspersed at irregular locationsthroughout at least a portion of the mask 2100. In some embodiments,holes of different diameters are evenly interspersed throughout at leasta portion of the mask 2100. For example, the mask 2100 can include aplurality of non-overlapping hole regions. The sum of the surface areaof the plurality of non-overlapping hole regions can equal to totalsurface area of the entire hole region of the mask. Each region of theplurality of regions can include a number of holes, each of the holeshaving a different diameter. The number of holes in each region canequal the number of different hole sizes in the entire hole region.

FIGS. 4A and 4B illustrate a cross section of a mold set 4000 having afirst lens forming mold portion 4002, a second lens forming mold portion(not shown), a positioning mold portion 4008, and/or a haptic shieldportion 4018. Each of the mold set components can be manufactured usingany suitable technique, including, but not limited to, an injectionmolding technique. In some embodiments, multiple such mold sets 4000 canbe combined into a mold assembly capable of manufacturing multiplelenses with embedded masks substantially simultaneously.

The first lens forming mold portion 4002 can include an interior lensforming surface 4004, an exterior surface 4006, a cavity 4024 forreceiving lens material, and/or a haptic region 4026. The first lensforming mold portion 4002 can include an outer edge portion 4022configured to join with the second lens forming mold portion and/or thepositioning mold portion 4008.

The cavity 4024 can be sized for the dimensions of the intraocular lens.For example, the cavity 4024 can include a diameter of at least about 5mm and/or less than or equal to about 6.5 mm. In certain embodiments,the cavity 4024 can include a diameter of about 6.0 mm. The diameter ofthe area including the cavity 4024 and the haptic region 4026 can be atleast about 10 mm and/or less than or equal to about 20 mm. In certainembodiments, the diameter of the area including the cavity 4024 and thehaptic region 4026 can be about 13.4 mm.

As shown in FIG. 4D, the second lens forming mold portion 4002 a can besubstantially similar, but complementary, to the first lens forming moldportion 4002 and can include a cavity for receiving lens material and/ora haptic region. The second lens forming mold portion 4002 a can includean outer edge portion configured to join with the outer edge portion4022 of the first lens forming mold portion 4002. When the second lensforming mold portion 4002 a is joined with the first lens forming moldportion 4002, they constitute a lens mold. The specific shapes, sizes,and surfaces of the first and second lens forming mold portions can bedesigned to fabricate a lens of a desired shape and size.

The positioning mold portion 4008 can include an outer edge portion 4020configured to join with the outer edge portion 4022 of the first lensforming mold portion 4002. The positioning mold portion 4008 can includean interior surface 4010 and an exterior surface 4012. The interiorsurface can include a protruding portion 4014, such as a protruding pin,extending from the interior surface 4010 of the positioning mold portion4008. The protruding pin 4014 can include a shoulder portion 4016 withan enlarged diameter where the protruding pin 4014 extends from theinterior surface 4010 of the positioning mold portion 4008. An annularmask 4028, such as those described herein, can be loaded onto theprotruding pin 4014 before the positioning mold portion 4008 and thefirst lens forming mold portion 4002 are joined. The protruding pin 4014can be transversely centered in the cavity 4024 to control the x-yposition of the annular mask 4028 within the intraocular lens, while theshoulder portion 4016 can be configured to control the depth of theannular mask 4028 within the intraocular lens.

As shown in FIG. 4B, the end portion of the protruding pin 4014 caninclude a diameter D₁. The diameter D₁ can substantially correspond toan internal diameter of the annular mask 4028. For example, the diameterD₁ of the end portion of the protruding pin 4014 can be within about 10microns of the internal diameter of the annular mask 4028, or withinabout 5 microns of the internal diameter of the annular mask 4028. Ifthe diameter D₁ is too small, the annular mask 4028 may not properlycenter in the intraocular lens along an x-y dimension, as there may beexcessive play between the annular mask 4028 and the protruding pin4014. If the diameter D₁ is too large, it may be difficult to separatethe annular mask 4028 from the protruding pin 4014 when the positioningmold portion 4008 is removed because of too tight of a fit. In someembodiments, the diameter D₁ can be at least about 1.1 mm and/or lessthan or equal to about 1.6 mm. In some embodiments, the diameter D₁ canbe at least about 1.3 mm and/or less than or equal to about 1.4 mm.

The protruding pin 4014 can have a length such that an end portion ofthe protruding pin 4014 is within a distance X₂ from the interiorsurface 4004 of the first lens forming mold portion 4002 when thepositioning mold portion 4008 is joined to the first lens forming moldportion. In certain embodiments, X₂ can be less than or equal to about0.3 mm, less than or equal to about 0.2 mm, or less than or equal toabout 0.1 mm. In certain embodiments X₂ can be about 0.1 mm. In certainembodiments, the distance X₁ from a base of the protruding pin 4014 tothe interior surface 4004 of the first lens forming mold portion 4002can be less than or equal to about 0.7 mm, less than or equal to about0.6 mm, less than or equal to about 0.5 mm, or less than or equal toabout 0.4 mm. In certain embodiments, the distance X₁ can be about 0.5mm. The length of the protruding pin 4014, from the shoulder portion4016, can be equal to X₁ less X₂ (X₁−X₂). In certain embodiments, thelength of the protruding pin 4014, from the shoulder portion 4016, canbe at least about 0.2 mm and/or less than or equal to about 0.6 mm. Incertain embodiments, the length of the protruding pin 4014, from theshoulder portion 4016, can be about 0.4 mm. It should be understood,however, that the specific dimensions of the protruding pin 4014 maydepend upon various factors, including the design and optical power ofthe IOL.

The diameter of the shoulder portion 4016 can be larger than the innerdiameter of the annular mask 4028, and can be configured to providesupport for the annular mask 4028 and still allow a sufficient amount oflens material to flow behind the annular mask 4028. The lens materialthat flows behind the annular mask 4028 can polymerize and helpstabilize the annular mask 4028 when the positioning mold portion 4008is removed, as discussed further herein.

The shoulder portion 4016 can include a substantially uniform diameteror a varying diameter. As shown in FIGS. 4A and 4B, the shoulder portion4016 can include generally rounded side portions and can include a basediameter D₃ that is greater than an end portion diameter D₂. Any portionof the shoulder portion 4016 can include a diameter within a range of atleast about 1.5 mm and/or less than or equal to about 2.5 mm. In someembodiments the diameter D₃ can be at least about 1.5 mm and/or lessthan or equal to about 2.5 mm. In certain embodiments, the diameter D₃can be at least about 2.0 mm and/or less than or equal to about 2.5 mm.In certain embodiments, the diameter D₃ can be about 2.1 mm. In someembodiments, D₂ can be at least about 1.5 mm and/or less than or equalto about 1.75 mm. In some embodiments, D₂ can be at least about 40% ofthe outer diameter of the annular mask 4028 and/or less than or equal toabout 60% of the outer diameter of the annular mask 4028. In certainembodiments, D₂ can be about 50% of the outer diameter of the annularmask 4028. In some embodiments, the difference between the diameter D₁of the end of the protruding pin 4014 and the diameter D₂ of theshoulder portion 4016 can be less than or equal to about 0.4 mm, lessthan or equal to about 0.2 mm, or otherwise.

The length X₃ of the shoulder portion 4016 can be configured to controlthe depth of the annular mask 4028 within the intraocular lens. In someembodiments, the length X₃ is designed such that the annular mask 4028is left substantially centered in the finished intraocular lens alongthe longitudinal axis of the lens. In some embodiments, the shoulderportion 4016 can include a length X₃ of at least about 0.15 mm and/orless than or equal to about 0.35 mm. In certain embodiments, the lengthX₃ can be about 0.25 mm. It should be understood, however, that thespecific dimensions of the shoulder portion 4016 may depend upon variousfactors, including the design and optical power of the IOL.

The first lens forming mold portion 4002 and the positioning moldportion 4008 can be joined together by, for example, lying one moldportion atop the other mold portion. In some embodiments, the hapticshield 4018 can be configured to join the positioning mold portion 4008or the first lens forming mold portion 4002. The haptic shield 4018 canbe configured to block light from entering a haptic region 4026 of themold during a photo curing stage of the manufacturing process. In somescenarios, if multiple doses of lens material are added to the mold andat least partially photo cured at different stages of the process, itmay be desirable to block light from entering the haptic region duringat least part of the curing process because later added doses of uncuredlens material can cause previously polymerized lens material to swelland buckle. As shown in FIGS. 4A and 4B, the haptic shield 4018 caninclude a body portion positioned over the outer edge portions 4020,4022 of the positioning mold portion 4008 and the first lens formingmold portion 4002. This configuration for the haptic shield 4018 can beused, for example, if curing light is provided on the positioning moldside of the assembly. FIG. 4C illustrates the haptic shield 4018positioned over the first lens forming mold portion 4002 (the first lensforming mold portion is flipped compared to its orientation in FIGS. 4Aand 4B). This configuration for the haptic shield 4018 can be used, forexample, if curing light is provided on the first lens forming mold sideof the assembly. In some embodiments, the mold set 4000 can include asupport rack 4030. As shown in FIG. 4C, the support rack 4030 caninclude a first and a second stepped region 4032, 4034 configured tosupport the respective ones of the positioning mold portion 4008 and/orthe haptic shield 4018.

FIGS. 5 and 6 are flow charts illustrating methods of manufacturing theintraocular lens. The methods can be used to embed an annular maskwithin the intraocular lens and ensure the proper centration and depthof the annular mask in the intraocular lens. None of the method stepsdisclosed should be understood as necessarily being essential orindispensable unless otherwise stated, and either method can includeadditional manufacturing steps.

FIG. 5 illustrates a method 5000 of manufacturing an intraocular lenswith an embedded annular mask using the mold set 4000 illustrated inFIGS. 4A and 4B. The method can include pre-dosing the first lensforming mold portion 4002 with a first amount of lens material (block5002). The method can include loading the annular mask, including any ofthe annular masks described herein, onto the protruding pin 4014 of thepositioning mold portion 4008 (block 5004). The method 5000 can includejoining the first lens forming mold portion 4002 and the positioningmold portion 4008 (block 5006), and at least partially curing the firstamount of lens material (block 5008). After partially curing the firstamount of lens material, the positioning mold portion 4008 can beremoved (block 5010), leaving the annular mask at least partiallyembedded in lens material. Aspects of each of these method steps aredescribed in further detail in connection with FIG. 6.

FIG. 6 illustrates a method 6000 of manufacturing an intraocular lenswith an embedded annular mask using the mold set 4000 illustrated inFIGS. 4A and 4B. The method can include pre-dosing a first lens formingmold portion 4002 with a first amount of lens material (block 6002). Thelens material can include any of the lens materials described herein,including, but not limited to, the hydrophobic materials disclosedabove.

In certain embodiments, the first amount of lens material can beequivalent to the amount of material necessary to completely fill thecavity 4024 and cause lens material to flow between the annular mask4028 and the positioning mold portion 4008. In this way, the annularmask 4028 is at least partially embedded in lens material on both sides,which can aid in avoiding longitudinal movement of the annular mask 4028when the first lens forming mold portion 4002 and the positioning moldportion 4008 are separated. If there is insufficient lens material tofill the cavity 4024, oxygen can be trapped in the mold, which can makeit difficult to cure the material because oxygen can inhibitpolymerization. In certain embodiments, the first amount of lensmaterial can be at least about 100 microliters and/or less than or equalto about 150 microliters.

In some embodiments, the lens material can include an ultraviolet lightabsorber to protect the eye from ultraviolet light. The lens materialcan also include a light-sensitive initiator to allow the lens materialto be photo cured by exposure to light. The light-sensitive initiatorcan include various biocompatible initiators, including, but not limitedto, acylphosphine oxide initiators, such as Irgacure® 819. While theultraviolet light absorption is a desirable feature of some embodimentsof the intraocular lens, some light-sensitive initiators react toultraviolet light. However, the presence of the ultraviolet lightabsorber could prevent such a light-sensitive initiator from beingeffective in a photo curing process. Thus, the initiator added to thelens material can be one that is activated when exposed to light havinga wavelength outside the absorption spectrum of the ultraviolet lightabsorber (e.g., visible light range, violet-blue light range, orotherwise). In certain aspects, the initiator can be activated by lighthaving a wavelength in a range from about 380 nm to about 495 nm. Incertain aspects, the initiator can be activated by a light having awavelength of about 420 nm. In certain aspects, the total amount oflight initiator can be less than or equal to about 0.25% of the totalamount of lens body material.

In block 6006, the first lens forming mold portion 4002 and thepositioning mold portion 4008 can be joined together, for example, asshown in FIGS. 4A and 4B. In certain embodiments, the shoulder portion4016 can be configured such that lens material can flow between asurface of the annular mask 4028 and the positioning mold portion 4008when the mold portions 4002, 4008 are joined together. In someembodiments, before joining the mold portions 4002, 4008, excess lensmaterial can be drained off.

In some embodiments, the haptic shield 4018 can be joined to the firstlens forming mold portion 4002 and/or the positioning mold portion 4008such that the haptic shield 4018 blocks light from reaching the hapticregion 4026 and prevents polymerization of the lens material within thehaptic region 4026 during certain curing stages of the fabricationprocess. In some embodiments, the haptic shield 4018 can join an outeredge portion 4020, 4022 of one or both of the mold portions 4002, 4008.The haptic shield 4018 can be positioned along the exterior surface 4012of the positioning mold portion 4008 or the exterior surface 4006 of thefirst lens forming mold portion 4002. In certain embodiments the hapticshield 4018 can be configured to be embedded within one of the moldportions 4002, 4008 or can be positioned within the haptic region 4026.

After joining the mold portions 4002, 4008, the lens material can be atleast partially cured (block 6010). For example, the lens material canbe cured less than a full cure, e.g., at least about 10% and/or lessthan about 50% of a full monomer conversion. The lens material can becured to a sufficient degree such that the annular mask 4028 remainswith the first lens forming mold portion after removing the positioningmold portion. In addition, the partially cured lens material between theannular mask 4028 and the positioning mold portion 4008 can help holdthe annular mask 4028 in place when the positioning mold portion 4008 isremoved.

In some embodiments, the cure can be performed using a light cure, forexample, using a 420 nm LED or any other suitable wavelength lightdescribed herein. Photo curing may be preferable to heat curing at thisstage of the fabrication process because it can allow for greatercontrol over the curing process. For example, a curing light can beturned on or off on command, which allows for fine control over thecure, whereas heat curing has more sluggish response times. In someembodiments, there can be a light intensity of at least about 0.5milliwatts/cm² and/or less than or equal to about 10 milliwatts/cm². Insome embodiments, the light intensity can be about 2 milliwatts/cm². Insome embodiments, the partial curing can take place for less than about10 minutes, less than about 6 minutes, less than about 5 minutes, orotherwise.

In some scenarios, the light can be applied to the positioning moldportion 4008. However, if the annular mask 4028 includes an ultravioletlight absorber, the annular mask 4028 can prevent ultraviolet light fromreaching the lens material, thereby inhibiting the partial curingprocess. In some embodiments, the mold set 4000 can be flipped overbefore the partial curing process or otherwise configured such that thelight can be applied to the first lens forming mold portion 4002 (whichcan be made from a material that is substantially transparent to thecuring light).

After partially curing the lens material, at least the first lensforming mold portion 4002 can be cooled (block 6012). The coolingprocess can increase lens material adhesion to the first lens formingmold portion 4002 and/or stiffen the partially cured lens material tohelp ensure that the lens material and annular mask 4028 stay with thefirst lens forming mold portion 4002 when the positioning mold portion4008 and/or haptic shield 4018 are removed (block 6014). In someembodiments, the cooling process can be used to cool the first lensforming mold portion 4002 by at least 20 degrees. In certainembodiments, the cooling process can be carried out using a cryogenicfluid, such as liquid nitrogen.

In some embodiments, the mold portions 4002, 4008 can be separated usinga machine-operated process to ensure that the mold portions 4002, 4008are vertically displaced without disrupting the position of the annularmask 4028.

The materials of the mold set 4000 can also be configured to help causethe annular mask 4028 to stay with the first lens forming mold portion4002 when the positioning mold portion 4002 is removed. For example, thefirst lens forming mold portion 4002 can include a material that adheresto the lens material to a greater extent, and the positioning moldportion 4008 can include a material that releases the lens materialand/or annular mask 4028 more easily. In certain embodiments, the firstlens forming mold portion 4002 can include a resin.

When the positioning mold portion 4008 is removed, the protruding pin4014 can leave behind a void that is substantially free of any lensmaterial. This void can be filled with uncured lens material when thesecond amount of lens material is added. The void left by the protrudingpin 4014 is in the region of the optical axis of the lens and extends toa depth near or at the interior lens forming surface 4004 of the firstlens forming mold portion 4002. Since the volume substantiallysurrounding the optical axis of the lens is filled with only the secondamount of lens material, the finished optic can include a homogeneousoptical material in the optical zone.

After removing the positioning mold portion 4008 and/or the hapticshield 4018, a second amount of lens material can be added to the firstlens forming mold portion 4002 and/or the second lens forming moldportion (block 6016), and the first lens forming mold portion and thesecond lens forming mold portion can be joined together (6018). In someembodiments, the second amount of lens material is sufficient tocompletely fill the volume between the first and second lens formingmold portions. In certain embodiments, the second amount of lensmaterial can be at least about 100 microliters and/or less than or equalto about 150 microliters. In certain embodiments, the second amount oflens material is about 150 microliters. After joining the first andsecond lens forming mold portions, the second amount of lens materialcan be allowed to diffuse through the partially cured first amount oflens material for a period of time (block 6020).

Following the diffusion period, the first and the second amount of lensmaterial can be at least partially cured (block 6022). The first and thesecond amount of lens material can be cured at least about 10% and/orless than about a 50% of a full conversion of monomer to polymer. Thepartial curing process helps stabilize the position of the annular mask4028 before the final cure. In some embodiments, the cure is performedusing a light cure, for example, using a 420 nm LED or any othersuitable wavelength light described herein. In some embodiments, thelight intensity can be at least about 0.5 milliwatts/cm² and/or lessthan or equal to about 10 milliwatts/cm². In some embodiments, the lightintensity can be about 2 milliwatts/cm². In some embodiments, the lightcuring process can take place for less time than the first partialcuring (block 6010). In some embodiments, the light intensity can beapplied for less than about 5 minutes, less than about 3 minutes, orotherwise.

The final curing process can be carried out using thermal curing (block6024). After the final cure, in some embodiments, the amount of leftoverresidual monomer can be less than 5% of the total amount of lensmaterial, less than 1% of the total amount of lens material, less than0.5% of the total amount of lens material, or otherwise, such that theresidual monomer does not need to be extracted. In certain embodiments,only about 0.3% of residual monomer remains after the final cure.

After the final curing process, the intraocular lens can be hydratedwith saline solution. As described above, the lens material can includea hydrophobic material. Hydrophobic lens materials can be useful becausea finished lens may take up less water when hydrated in saline solutionthan lenses made of hydrophilic materials. If the lens body were to takeup too much water, the lens body could swell and disrupt the positioningof the mask and/or damage the mask embedded within the intraocular lens.In certain embodiments, the intraocular lens material can include awater content of less than about 4%, or less than about 3%. In certainembodiments, the intraocular lens material can include a water contentof about 2.5%.

In some embodiments, after the lens is removed from the mold set, it canbe machined on either side or on both sides. For example, one side canbe cut to the proper shape and then both sides can be polished. In someembodiments, the side of the lens to be cut is the side formed by thesecond lens forming mold portion.

Various embodiments have been described above. Although the inventionhas been described with reference to these specific embodiments, thedescriptions are intended to be illustrative and are not intended to belimiting. Various modifications and applications may occur to thoseskilled in the art without departing from the true spirit and scope ofthe invention as defined in the appended claims.

1-23. (canceled)
 24. A method of manufacturing an intraocular lens, themethod comprising: adding a first amount of a lens material to a firstmold portion; positioning a mask with an aperture on a shoulder portionof a protruding pin of a positioning mold portion, the shoulder portionconfigured to control a depth of the mask in the intraocular lens;joining the first mold portion and the positioning mold portion; andpartially curing the first amount of the lens material.
 25. The methodof claim 24, wherein a diameter of the shoulder portion is larger than adiameter of the aperture of the mask.
 26. The method of claim 24,wherein the shoulder portion extends from an interior surface of thepositioning mold portion.
 27. The method of claim 24, wherein joiningthe first mold portion and the positioning mold portion causes lensmaterial to flow into a space between a surface of the mask and an innersurface of the positioning mold portion so as to at least partiallysurround the mask with lens material on both of its sides.
 28. Themethod of claim 24, wherein the lens material comprises an ultravioletlight absorber and a light-sensitive initiator, the light-sensitiveinitiator being configured to cure the lens material when exposed tolight having a wavelength outside the absorption spectrum of theultraviolet light absorber.
 29. The method of claim 28, wherein thelight-sensitive initiator is configured to be activated by light havinga wavelength in a range from about 380 nm to about 495 nm.
 30. Themethod of claim 24, wherein partially curing the first amount of thelens material comprises applying light to the first mold portion. 31.The method of claim 24, wherein partially curing the first amount of thelens material comprises curing the first amount of the lens material toa sufficient degree that the mask remains with the first mold portionafter removing the positioning mold portion.
 32. The method of claim 24,further comprising cooling the first mold portion.
 33. The method ofclaim 32, wherein cooling the first mold portion comprises cooling thefirst mold portion using a cryogenic fluid.
 34. The method of claim 32,wherein cooling the first mold portion comprises reducing a temperatureof the first mold portion by at least 20 degrees.
 35. The method ofclaim 24, further comprising removing the positioning mold portion andjoining the first mold portion and a second mold portion.
 36. The methodof claim 35, further comprising adding a second amount of the lensmaterial to the second mold portion.
 37. The method of claim 36, furthercomprising partially curing the second amount of the lens material byexposure to light.
 38. The method of claim 37, further comprising, afterpartially curing the second amount of the lens material by exposure tolight, thermally curing the second amount of the lens material.
 39. Themethod of claim 38, further comprising polymerizing at least 99% of thefirst and second amounts of the lens material.
 40. The method of claim24, wherein the lens material is a hydrophobic material.
 41. The methodof claim 24, further comprising joining a haptic shield and thepositioning mold such that the haptic shield prevents polymerization ofthe lens material in a haptic region.